相关论文: Resistively controlled primordial magnetic turbule…
The decay of magnetically dominated turbulence exhibits robust inverse transfer of magnetic energy even in the absence of net magnetic helicity, challenging traditional cascade-based phenomenology. While recent studies suggest that magnetic…
We present a new theoretical picture of magnetically dominated, decaying turbulence in the absence of a mean magnetic field. We demonstrate that such turbulence is governed by the reconnection of magnetic structures, and not by ideal…
The decay of a turbulent magnetic field is slower with helicity than without. Furthermore, the magnetic correlation length grows faster for a helical than a nonhelical field. Both helical and nonhelical decay laws involve conserved…
We investigate the impact of turbulence on magnetic reconnection through high-resolution 3D magnetohydrodynamical (MHD) simulations, spanning Lundquist numbers from $S=10^3$ to $10^6$. Building on Lazarian and Vishniac's (1999) theory,…
The Saffman helicity invariant of Hosking and Schekochihin (2021, PRX 11, 041005), which we here call the Hosking integral, has emerged as an important quantity that may govern the decay properties of magnetically dominated nonhelical…
The Hosking integral, which characterizes magnetic helicity fluctuations in subvolumes, is known to govern the decay of magnetically dominated turbulence. Here we show that, when the evolution of the magnetic field is controlled by the…
It has been recently shown numerically that there exists an inverse transfer of magnetic energy in decaying, nonhelical, magnetically dominated, magnetohydrodynamic turbulence in 3-dimensions (3D). We suggest that magnetic reconnection is…
We present Direct Numerical Simulations of decaying Magnetohydrodynamic (MHD) turbulence at low magnetic Reynolds number. The domain considered is bounded by periodic boundary conditions in the two directions perpendicular to the magnetic…
We propose a mechanism whereby the intense, sheet-like structures naturally formed by dynamically aligning Alfv\'enic turbulence are destroyed by magnetic reconnection at a scale $\hat{\lambda}_{\rm D}$, larger than the dissipation scale…
Magnetic reconnection is best known from observations of the Sun where it causes solar flares. Observations estimate the reconnection rate a small, but non-negligible fraction of the Alfv\'en speed, so-called fast reconnection. Until…
Powerful lasers may in future produce magnetic fields that would allow us to study turbulent magnetohydrodynamic inverse cascade behavior. This has so far only been seen in numerical simulations. In the laboratory, however, the produced…
Magnetic field fluctuations in MHD turbulence can be viewed as current sheets that are progressively more anisotropic at smaller scales. As suggested by Loureiro & Boldyrev (2017) and Mallet et al (2017), below a certain critical thickness…
We use extensive 3D resistive MHD simulations to study how large-scale current sheets will undergo fast reconnection in the high Lundquist number $S$ limit (above $\sim 10^4$), when the system is subject to different externally driven…
We show that in decaying hydromagnetic turbulence with initial kinetic helicity, a weak magnetic field eventually becomes fully helical. The sign of magnetic helicity is opposite to that of the kinetic helicity - regardless of whether or…
Decay of honeycomb-generated turbulence in a duct with a static transverse magnetic field is studied via direct numerical simulations. The simulations follow the revealing experimental study of Sukoriansky et al. (1986), in particular the…
It has been established that the Sweet-Parker current layer in high Lundquist number reconnection is unstable to the super-Alfv\'enic plasmoid instability. Past two-dimensional magnetohydrodynamic simulations have demonstrated that the…
The current understanding of MHD turbulence envisions turbulent eddies which are anisotropic in all three directions. In the plane perpendicular to the local mean magnetic field, this implies that such eddies become current-sheet-like…
Dynamical studies of MHD turbulence on the one hand, and arguments based upon magnetic helicity on the other, have yielded seemingly contradictory estimates for the $\alpha$ parameter in turbulent dynamo theory. Here we show, with direct…
The inverse cascade in MHD turbulence plays a crucial role in various astrophysical processes such as galaxy cluster formation, solar and stellar dynamo mechanisms, and the evolution of primordial magnetic fields in the early universe. A…
Magnetic reconnection, topological change in magnetic fields, is a fundamental process in magnetized plasmas. It is associated with energy release in regions of magnetic field annihilation, but this is only one facet of this process.…